This is a simple non-recursive delete operation.  It prunes paths
of empty nodes in the tree, but it does not try to further compress
the tree as nodes are removed.
Signed-off-by: NCraig Gallek <kraig@google.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>